Republicans will have to accept some sort of tax increase in order to avoid the so-called fiscal cliff, Missouri Sen. Claire McCaskill, D-Mo., said in her first interview since Election Day.

McCaskill was back at work on Capitol Hill Wednesday after winning a hard-fought reelection campaign against Republican challenger Todd Akin.

Last week’s election results prove that Americans agree that those in top income brackets should pay a little more in taxes, she said.

"I have voted in the past, and I will vote again to raise the tax rates on those at the very top, whether the line is 250, or if the line is 500, or if the line is $1 million." McCaskill said.

Democrats propose raising tax rates on family incomes above $250,000. She was also referring to the possibility of raising tax rates on incomes above $500,000 or $1 million.

“Closing loopholes is a good thing too but you can’t really get where you need to go by just closing loopholes,” she said.

McCaskill acknowledged that painful budget cuts will be necessary, but some programs should be off the table, as far as she’s concerned. “I’m not going to be a pushover,” she said.

“I’m not interested in privatizing Medicare and not interested in making Social Security part of this particular discussion, and I’m not interested in welching on the promises we made to veterans,” she added.

But McCaskill pledged to keep an open mind. She said she will work with senators from both parties to move forward.

“I would love to show America that we can get this place to work and that will not happen if people are still focused more on winning elections than they are on getting things done,” she said.

McCaskill also mentioned that she had attended a classified briefing on Wednesday about the fatal attack on a U.S. consulate in Benghazi, Libya, on Sept. 11. Four Americans were killed in the attack, including Ambassador Chris Stevens.

She said she now knows more about the facts, and while she has concerns that lessons need to be learned and additional steps taken to ensure there isn’t a repeat, she worries that the tragedy is being used for political leverage. A group of Republicans on Wednesday called for the formation of a select committee to investigate the circumstances surrounding the attack.

"I am troubled with what feels like politicizing this issue more than it should be politicized," McCaskill said. "I have no problem with aggressive oversight, but I want to make sure that we don’t cross the line of aggressive oversight into politicizing what was a tragedy.” Congress needs to “make sure we’re looking forward instead of playing a blame game," she added.

One of an unprecedented 20 women elected to the next Senate, she said Wednesday that she found herself in a traffic jam with four other female colleagues in the ladies’ bathroom in the Capitol building. “I said, ‘We’re going to need a bigger bathroom,’” she joked.

“It’s great to have this many women and I look forward to getting to know the women better who have joined the Senate,” McCaskill said.